TENERIFFE, the name of one of the Canary Islands, situated on the west coast of Africa. In a long article on the CANARY ISLANDS in Vol. V. p. 259-265 we have already treated most of the general topics which relate to this island, and it remains only to notice some particulars which may be ex pected under the present article.
Teneriffe is of a triangular form, each side being about thirty-six miles in length, and chiefly consists of the Great Peak sloping down into the sea. It contains about 1540 square miles or 985,600 acres. It is divided in the middle by a ridge of mountains which have been likened to the roof a church, the peak forming the spire in its centre. Five-sixths of the island has been computed to consist of rocks, woods, and inaccessible mountains. According to Humboldt, the height of the peak is 1909 toises, or about 12,090 feet. The size of the crater on the summit is only 300 feet by 200, and its depth does not exceed 100 feet. The island is almost wholly volcanic, resting on a submarine volcano. The range of basaltic rocks which surround the island do not rise to a greater height than 500 or 600 toises, and through the midst of this formation the rocks which constitute the principal mass of the volcano, have been protruded from below. Accord ing to Dr. Daubeny, the modern lavas may be di vided into two classes ; 1st, Those which compose the nucleus of the mountain, and are of a trachytic character, have been forced up through the older basalt ; and, 2dly, The products of the volcanic ac tion to which this central mass furnished a vent. The last class are various. Those which have a stony aspect are low in position, and seem to have come from the flanks of the volcano, while the vitreous ones occur only near the summit at heights exceeding 8900 feet. They seem to have come from the adjoining mountain Chahorra, which is to the peak what Monte Rossi is to Mount /Etna, having been produced by a lateral eruption.
Von Buch is of opinion, that the great chimney in the peak preserves the island from those de structive eruptions which convulse some of the neighbouring ones ; but though it may act as a safety valve, yet, as Dr. Daubeny observes, it is a dangerous neighbour to the towns at its base. In
1704 and 1706 lateral eruptions took place, which destroyed the harbour of Garachico, the best fre quented harbour in the island. In 1798 Chahorra ejected lavas and scoriae for three months, and as some of the fragments took from twelve to fifteen seconds to descend, they must have risen to the height of 3000 feet. Smoke constantly issues from the summit of the peak, and though it is never known to emit flames, yet sulphurous acid vapours are constantly exhaled from it, from several aper tures near the lowest part of the crater. The inte rior of the crater is covered with yellow and white clay, and fragments of decomposed lava, under which are found beautiful octohedral crystals of sulphur.
Teneriffe is remarkable for the excellence of its climate, varying from the heat of the equinoxial regions to the colder climates of Europe. The scenery of the island is remarkable for its beauty. The date tree, the plantain, the sugar cane, the In dian fig, and the olive tree are cultivated. Wheat is reaped from the end of March to the beginning of May, and the bread fruit tree, and the cinnamon, cocoa, and coffee plants have been successfully cul tivated. Above this productive region rises the re gion of the laurels, then the chestnut plantations, then the vast forests of pines, then the vast plain, like a sea of sand adorned with the odoriferous re lama, and lastly the 1\Ialpays, covered with loose fragments of lava. At the extremity of the Mal pays is the plain of Rambleta, with the crevices which discharge watery and heated vapours. Po pulation about 100,000. For farther information respecting this island, see Captain Cook's Third Voyage, vol. i. p. 22; and Embassy to China, vol. i. La Perousc's Voyage, vol. ii. p. 226 ; Mr. Grey 13ennet in the Geological Transactions, vol. ii. ; Humboldt's Personal .1Varrat:vc ; Daubeuy's De scription of Sctivc and Extinct Volcanos, p. 251 ; but particularly Baron Leopold Von Buch's Physi calischc Ilcschrcibung der Canarischen Juselm, Ber lin, 1825, 1 vol. 4to, and a folio volume of Charts and Plates. See also the article CANARY ISLES, and the works there referred to.